Secondary electric clock



F. FRICK.

SECONDARY ELECTRIC CLOCK.

APPLlCATlON FILED SEPT. 29, 1920.

Patented Aug. 23, 1921.

2 SHEETS-SHEET 1.

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SECONDARY ELECTRIC CLOCK. APPLICATION FILED SEPT.29, 1920.

I 1,388,458. Patented Aug". 23, 1921.

2 SHEETSSHEET 2.

v the minute shaft UNITED STATES PATENT oFF cE.

FREDERICK ERICK; OF WAYNESIBORO, PENNSYLVANIA.

SECONDARY ELECTRIC 01.003.

To whom it may eoncem: ,c

Be it known that I, FREDERICK FRIoK, a citizen of the United States, and residing at WVaynesboro, Franklin county, State of Pennsylvania, have invented certain new and useful Improvements in Secondary Electric Clocks, of which thefollowing is a specification. i

The object of the present invention is to provide a simple, compact, inexpensive and easily manufactured electric secondary clock which is silent in operation, and may be placed in hotel sleeping rooms, school rooms, ofiices, and in any locations Where it is desired to have a clock, but also essential that there be no mechanical sounds to disturb the inmates of theroom or ofi'ice.

It has heretofore been attempted to provide silent secondary clocks, but clocks of this class heretofore designed or suggested have been relatively expensive, bulky, in-

convenient to install and repair, and difii-,

cult to manufacture. The present invention contemplates a clock of this character which. is silent in operation, having no limiting stops for the moving parts whereby mechanical sounds are made, and which is thoroughly efiicient and practical, not only from the clock 'designers point of view, but also from the manufacturers point of view.

One embodiment of the invention will be fully disclosed. in the following description whentaken in connection with the accompanying drawings, in which- Figure 1 is a-rear view of the clock, the rear plate having .been removed; Fig. 2 is central vertical section, taken on line 2-2 of Fig. 1; and

Fig. 3 is a rear elevation of a modified form of clock, the rear plate having been removed. Referring to Figs. 1 and 2 of the drawings, and the. hour sleeve are 11 respectively, the usual reducing gearing at R, and a large gear frictionally secured to shaft 10by the friction spring 12, at 13, this gear being. rigidly connected to the adjacent pinion of the reducing gearing and meshing with a pinion 14 fast on shaft 15, the last mentioned shaft bein rotatably mounted in the frame.

ounted on shaft 15 for rotationtherewith is a large gear 16 which meshes with indicated at 10 and a pinion 17 mounted on rotatable shaft 18- Specification of Letters Patent.

ing between the pinion 17 on the .fore, causes the rotation of Patented Aug. 23, 1921.

Application filed September 29,1920. Serial m5. 413,502.

M, M and when these magnetsare energized, the armature is constrained to revolve so that its main central or diametrical portion is horizontal. Also fixed on shaft 18 is a gear 21 which meshes with a, gear 22, the diameter of which is exactly half as great, the gear 22 being mounted on sleeve 23 which is rotatably supported on the frame, and having an'ann-ular flange or crank 24 at its rear end carrying a pin or stud25.

Upon stud 25 is rotatably secured a member 26 and this member is connected to the lower part of the frame by two coiled tension springs 27, 27 which constantly tend to keep stud 25 in its lowermost position, and hence to keep armature 19 in the position illustrated in Fig. 1, with the axis of-its main portion inclined to the vertical. As before stated, the diameter of gear 22 is exactly half as great as the diameter of gear 21 and when the latter gear revolves once, the former will of course, revolve twice. The geararmature shaft 18 and the reducing gearing R is preferably so designed that for each half revolution of pinion 17, the minute hand will be advanced one space or one minute and the hour. hand one-twelfth of a revolution or one hour.

In the operation of the clock thecircuit is completed at the master clock (not illustrated once each minute, energizing magnet coils ,M-and causing the rotation of armature 19 through an angle greater than 90 but less than 180, as can be seen by an inspection of Fig. 1. This causes the rotation of gear 21 through more than 90 and, theregear 22 to .rotate more than 180, against the action of the springs, so that stud 25 will Have moved (in the direction of the arrow, Fig. 1) to the osition illus- .trated in dotted lines. Imme iately on the deenergization of the magnets M, M the springs 27, 27 will be effective to continue gear 22 to full line position (Fig. 1), and in thus returning gear 22 to this position, gear 21 and armature 9 are alsometurned to their original positio s and the h The noiseless, there being no.1imiting stops determining the extent of movement of the armature or any of the gears, and the clock maybe positioned at any point where a noiseless clock is required- The various parts are simple in desi and ma be inexpensively manufacture and easi y assemands advanced a complete minute space. movement .of the parts is absolutely bled together. The clock may also be made very small in size if desired.

In the modified form of clock illustrated in Fig. 3, a light crank arm24 is substituted for the disk 24: illustrated in Figs. 1 and 2, and the springs 27, 27' are positioned below cross pieces '30, 30 extending between the front and back plates, the springs being confined between .plates 31, 31 and 32, 32, the upper plates being secured to the cross pieces 30, 30 and the lower plates being tied y light wires or rods 33, 33 to the member 26, the Wires 33, 33 extending through the coiled springs and through suitable apertures in the top plates 31, 31 and cross pieces 30-, 30. The Weight and inertia of the moving parts are materially reduced in this construction, a'nd the tendency of the mechanism to vibrate the hands after the completion of the movement practically eliminated.

It will be obvious to one skilled in the art that the design and arrangement of the various parts of the invention may be greatly modified, and that the invention is not limited to the two embodiments shown and described. The number and position of the springs may be changed as desired, and the silent mechanism may be utilized in combination with clocks having widely different structures from that illustrated.

Having thus described the invention what is claimed as new and desired to be secured by Letters Patent is:

1. In a secondary clock a device for in-. termittently rotating'a shaft comprising in combination means for rotating said shaft through an angle less than 180, and means for completing the rotation of said shaft through 180, said last mentioned means including a member rotatable about an axis displaced from the axis of said rotatable shaft and operatively connected to said shaft and a resilient element connected to said member.

2. In asecondary clock a device for intermittently rotating a shaft comprising in combination, means for rotating said shaft through an angle less than 180, and second means for completing the rotation of said shaft through 180, including a member rotatably mounted on an axis displaced from the axis of said rotatable shaft and operatively connected to said shaft and resilient means connected to said member.

3. In a secondary clock a device for intermittently rotating a shaft comprisim in combination, means for rotatiri said shaft through an angleless than 180,, and second means for completing the rotation of said shaft through 180, including a gear mounted on the shaft, a second gear meshing with said first gear and resilient means normally tending to maintain said second gear in a definite position.

1. In a secondary clock a device for intermittently rotating a shaft comprising in combination, electromagnetic means for rotating said shaft through an angle less than 180, and means for completing the r0- tation of said shaft through 180, said last mentioned means including a member rotatable about an axis displaced from the axis of said rotatable shaft 'and operatively connected to the shaft and a resilient element connected to said member.

5. In a secondary clock, a device for intermittently rotating a shaft comprising in combination, an electromagnet having pole pieces spaced on opposite sides of the shaft. a Z-shaped armature mounted on the shaft and so arranged that the armature and shaft will rotate between 90 and 180 when the magnet is energized, and means for completing the rotation of the shaft through 180 when the magnet is deenergized said means including a member rotatable about an axis displaced from the axis of said rotatable shaft and operatively connected to said shaft and a resilient element connected to said member.

6. In a secondary clock a device for intermittently rotating a shaft comprisin in combination, means for rotating said shaft through an angle less than 180, and means for, completing the rotation of said shaft through 180, including a gear mounted on the shaft, a second gear meshing with said first gear, and a plurality of springs normally tending to maintain said second gear in a definite position.

7. In a secondary clock a device for intermittently rotating a shaft comprising in combination, means for rotating said shaft through an angle less than 180, and means for completing the rotation of said shaft through 180, including a gear mounted on the shaft, a second gear meshing with said first gear, a wire member connected to said second gear, and resilient means normally tending to draw said wire member in one direction to maintain said gear in a definite position.

8. In a secondary clock a device for intermittently rotating a shaft comprising in combination, means for rotating said shaft through and angle less than 180, and means for completing the rotation of said shaft through 180, including a gear mounted on the shaft, a second gear meshing with said first gear, a plurality of wire members connected to said second gear and extending substantially radially therefrom, and a spring associated with each of said wire members and tending to draw it in one direction to maintain said gear in a definite position.

In testimony whereof I affix my signature.

FREDERICK FRICK. 

